In one embodiment, the cross slope created by an earth moving machine, such as a motor grader, may be described as the slope of a line lying on a surface path, such as a road, which is perpendicular to the direction of the path. Cutting an accurate cross slope into a land site is an important function for an earth moving machine such as a motor grader. Therefore, it would be advantageous to accurately determine the cross slope. The measured cross slope may be provided to an operator, or compared to a desired cross slope in order to determine if the machine is creating the appropriate slope, and make adjustments to the blade position if a position error is occurring.
Some previous implementations of systems determining cross slope created by the blade, utilize GPS and laser technology to determine position of the blade and the machine relative to the land site, thereby enabling an cross slope of cut of the blade to be determined. However, these systems require GPS and laser detection systems that can be expensive, and are not easily implemented in remote sites, such as cutting a road in a remote location.
In addition, some previous implementations of systems that do not utilize GPS and laser technology, do use techniques which provide inaccurate information. For example, determining an angle of rotation of the blade may be used to ultimately determine the cross slope. Some implementations determine an angle of rotation of the blade relative to the direction of travel of the blade using measuring means which include velocity transducers, example radar guns, for measuring the ground velocity in the direction of travel of the blade. However these systems are expensive, and have associated inaccuracies, due in part, to the fact that the accuracy decreases as the measured velocity approaches zero.
In addition, some previous implementations did not account for the appropriate variables. Sensing too few parameters leads to inaccurate results.
The present invention is directed to overcoming one or more of the problems as set forth above.